Pension and Other Postretirement Benefit Plans (Change in Benefit Obligation) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Jun. 30, 2011	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
United States Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Benefit obligation, beginning of year		$ 3,546	$ 4,196
Service cost		2	2	2
Interest cost		167	162	178
Plan participants’ contributions		0	0
Actuarial loss (gain)		384	(420)
Benefits paid		(303)	(281)
Plan amendments		0	0
Acquisitions		0	0
Transfer of benefits		0	(105)
Settlements / curtailment (gain)		0	(8)
Foreign currency exchange rates		0	0
Benefit obligation, end of year		3,796	3,546	4,196
Accumulated benefit obligation, end of year		3,786	3,536
Foreign Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Benefit obligation, beginning of year		439	448
Service cost		5	6	6
Interest cost		22	17	20
Plan participants’ contributions		1	1
Actuarial loss (gain)		59	(7)
Benefits paid		(24)	(23)
Plan amendments		(3)	0
Acquisitions		610	0
Transfer of benefits		0	0
Settlements / curtailment (gain)		(15)	(6)
Foreign currency exchange rates		(68)	3
Benefit obligation, end of year		1,026	439	448
Accumulated benefit obligation, end of year		964	424
Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Benefit obligation, beginning of year		509	477
Service cost		3	4	5
Interest cost		24	18	21
Plan participants’ contributions		7	8
Actuarial loss (gain)		9	(31)
Benefits paid		(60)	(68)
Plan amendments	138	14	2
Acquisitions		0	0
Transfer of benefits		0	105
Settlements / curtailment (gain)		0	0
Foreign currency exchange rates		(4)	(6)
Benefit obligation, end of year		$ 502	$ 509	$ 477